In September 1862 there was a crisis in Prussia where the Prussian Landtag, or lower parliamentary house, was refusing to approve increased military spending in defiance of the King's wishes. King Wilhelm I was advised by his Minister of War, Roon, to send for Bismarck as a formidable personality who might secure the passing of the military budget in the Landtag.
On the 17 September the crisis had reached such a pitch that Wilhelm I seriously considered abdicating his throne. That evening Roon sent by telegraph to Bismarck suggesting that he, Bismarck, should hurry to Berlin and that there was danger in delay. The message in French and Latin read :- Depechez-vous; Periculum in mora.
On 22 September Bismarck met Wilhelm I and assured him that he could form a ministry and carry through the army reforms as he desired, if necessary against the will of the deputies in the Landtag. Given this assurance the Wilhelm I decided not to abdicate. Bismarck was appointed acting chief minister of Prussia.
Bismarck made an appearance before the Landtag on 29 September where he spoke expressing his regret at the hostility of the deputies to passing of the military budget and stressed the need for progress to be made on the military proposals favoured by the king. The next day at a meeting of a Budget Committee Bismarck went perhaps further than he his better judgement might have intended in asserting that:-
The position of Prussia in Germany will not be determined by its liberalism but by its power ... Prussia must concentrate its strength and hold it for the favourable moment, which has already come and gone several times. Since the treaties of Vienna, our frontiers have been ill-designed for a healthy body politic. Not through speeches and majority decisions will the great questions of the day be decided - that was the great mistake of 1848 and 1849 - but by iron and blood. This Speech by Bismarck has entered into popular understanding of history as ending blood and...